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de Jesus Perez, V.

Publications and source records attributed to de Jesus Perez, V..

3 recordsLinked to original sources

Microvascular preservation and cardiomyocyte hyperplasia underlie adaptive right ventricular development in congenital heart disease-associated pulmonary arterial hypertension

AbstractO_ST_ABSBackgroundC_ST_ABSRight ventricular (RV) failure is the primary cause of death among patients with pulmonary arterial hypertension (PAH). Patients with congenital heart disease- associated PAH (CHD-PAH) demonstrate improved outcomes compared to patients with other forms of PAH, which is related to the maintenance of an adaptively hypertrophied RV. In an ovine model of CHD-PAH, we aimed to elucidate the cellular, microvascular, and transcriptional adaptations to congenital pressure overload that support RV function in CHD-PAH. MethodsFetal surgery was performed on late gestation lambs to insert a large aortopulmonary graft, leading to a persistent congenital left-right shunt and RV pressure load. At 3 days and 4-6 weeks of life, shunt RV microvasculature, cardiomyocyte structure, and myocardial growth mechanisms were compared to age-matched controls and unoperated fetal RV. RNA sequencing was performed to assess differences in the RV transcriptomes. ResultsAt 4-6 weeks of age, shunt lambs demonstrate significant RV enlargement (shunt 37.1 {+/-} 2.9g vs control 15.9 {+/-} 1.0g, p<0.001) but maintain stable microvascular density (fetal 3.0 {+/-} 0.6 vs shunt 2.9 {+/-} 0.3 vs control 3.1 {+/-} 0.6 capillaries per 1000 {micro}m3, p>0.05). Shunt RV cardiomyocytes are significantly smaller by cross-sectional area and more numerous than age-matched controls (shunt 73.3 {+/-} 5.5 {micro}m2 vs control 99.2 {+/-} 4.9 {micro}m2, p=0.013). At 3 days, shunt RV cardiomyocytes show evidence of increased proliferative capacity and ongoing hyperplasia compared to controls. RNA sequencing analyses reveal a distinct gene expression profile in shunt RV consistent with a delay in terminal differentiation and metabolic adaptations to support adaptive function. ConclusionsThis study provides novel insights into the development of adaptive RV hypertrophy in CHD-PAH, demonstrating roles for preserved microvascular density and increased postnatal cardiomyocyte hyperplasia in supporting RV performance. Future investigations into the mechanisms underlying these changes could have significant implications for the development of novel therapeutic strategies for supporting RV function.

physiology↗

Adventitial fibroblasts direct smooth muscle cell-state transition in pulmonary vascular disease

Pulmonary vascular remodeling is a progressive pathological process characterized by functional alterations within pulmonary artery smooth muscle cells (PASMC) and adventitial fibroblasts (PAAF). Mechanisms driving the transition to a diseased phenotype remain elusive. Utilizing a combination of transcriptomic and proteomic profiling, along with phenotyping of source-matched cells from healthy controls and individuals with idiopathic pulmonary arterial hypertension (IPAH), our investigation uncovered that while PASMC and PAAF retained their original cellular identities, they acquired distinct disease-associated states. Though both cell types exhibited reduced mitochondrial content and hyperpolarization, IPAH-PASMC displayed heightened glycosaminoglycan production and downregulation of contractile machinery, contrasting a hyperproliferative phenotype of IPAH-PAAF. We investigated the involvement of cellular crosstalk in regulating cell state dynamics and identified pentraxin-3 and hepatocyte growth factor as potential modulators of PASMC phenotypic transition orchestrated by PAAF. Our findings contribute to a deeper understanding of pulmonary vascular mesenchyme dynamics in disease pathogenesis.

cell biology↗

Specialized Pericyte Subtypes in the Pulmonary Capillary

Pericytes (PCs) play crucial roles in capillary maturation, stability, and homeostasis. Impaired PC coverage and function are implicated in various diseases, including pulmonary arterial hypertension (PAH). Challenges investigating PC biology are largely due to the lack of a concise marker, resulting in difficulty distinguishing PCs from other mural cell populations, including smooth muscle cells (SMCs) and fibroblasts (FBs). Utilizing bioinformatic analysis and RNAscope, we identified HIG hypoxia-inducible domain family member 1B (Higd1b) as a unique and conserved gene marker for PCs and generated a novel knockin mouse line, Higd1b-CreERT2, which precisely labels PCs in the lung and heart. Human lung single-cell RNAseq suggested the presence of two HIGD1B+ PC subtypes with different functions. By lineage tracing pulmonary Higd1b+ cells exposed to hypoxia in vivo, we identified Type 1 PCs remained in the capillary network, while Type 2 PCs accumulated in the arterioles and coexpressed SMC markers and increased levels of Vimentin, associated with focal adhesion pathways. These results suggest that Type 1 PCs are specialized for supporting capillary EC homeostasis and quiescent, while Type 2 PCs are lineage active and located close to the border zone of the arterioles and capillaries, which may be motile and transition to SMC-like cells in hypoxia-induced pulmonary hypertension. The discovery of PC-type specialization in capillaries transforms our understanding of the structure, function and regulation of pulmonary capillary circulation and their contribution to vascular remodeling.

cell biology↗